In manufacturing wood materials such as a plywood, a particle board and a fiberboard or in manufacturing furniture, building materials, etc. from the wood materials, a formaldehyde-based adhesive is sometimes used. In this case, formaldehyde liberated from such an adhesive is emitted from the wood building materials, or furniture, building materials, etc. However, recently, houses have become more and more airtight and accordingly formaldehyde causes health damage such as sick house syndrome.
Also in manufacturing interior materials for vehicles such as vehicle seats, the formaldehyde-based adhesive is sometimes used. In this case, a vehicle room is narrower than an ordinary house and much more airtight than an ordinary house and therefore severer damage is caused by formaldehyde.
Furthermore, other than these, heat insulators, buffer materials and insulation materials are manufactured by immobilizing glass wool, rock wool, etc. with the formaldehyde-based adhesive, and used as interior materials for general houses, buildings, factories, warehouses, etc. Formaldehyde is also emitted from these materials and pollutes living spaces slightly.
In the circumstances, a formaldehyde scavenger for scavenging and decomposing formaldehyde has been conventionally known. As the formaldehyde scavenger, urea is generally known.
Urea is an inexpensive formaldehyde scavenger, but a disadvantage thereof is that scavenged formaldehyde is reemitted by hydrolysis with heat or the like.
Furthermore, as the formaldehyde scavenger, formaldehyde scavengers containing ammonium phosphate monobasic and ammonium phosphate dibasic are known (see Japanese Patent Laid-Open No. 2007-191575).
However, such conventional formaldehyde scavengers containing ammonium phosphate monobasic and ammonium phosphate dibasic do not always provide sufficient formaldehyde scavenging performance.
Moreover, as the formaldehyde scavenger, an aldehyde deodorizing composition containing urea and at least one ammonium salt selected from ammonium phosphate monobasic, ammonium phosphate dibasic and ammonium sulfate is known (see Japanese Patent Laid-Open No. 2007-313300).
However, Japanese Patent Laid-Open No. 2007-313300 does not specifically describe that the aldehyde deodorizing composition is applied to wood materials.